hanging idle....i think

Got questions? We got answers....
Post Reply
zkdx
Member
Posts: 26
Joined: 03:02 pm Aug 01 2005
Country:
Location: Arkansas

hanging idle....i think

Post by zkdx »

I think I have what I've heard called a hanging idle. Basically seems like it doesn't want to calm down and idle correctly. I no it's not just my idle set high, because the bike will set on idle for a little bit, then it catches it's breath and speeds up again. I am very new to this particular bike, and have made no jetting changes yet, nor can I remember what is in it. BTW 91 kdx 200. I guess my real question is what exactly is a hanging idle and where to you look for a cure? Is it sucking air from somewhere, the boots both look good, should I be looking elsewhere.
04' WR250F--All the standard mods
91' KDX200 (a.k.a. The White Ghost)--not much done yet
01' XR80-kids
01' XR50-kids
85' GS550E--For Sale
User avatar
KDXGarage
KDXRider.net
KDXRider.net
Posts: 14060
Joined: 06:45 am Nov 01 2004
Country: United States of America
Location: AL, USA
Contact:

Post by KDXGarage »

Have you taken the carb apart and inspect / cleaned it yet? That's always a good place to start.
Thank you for participating on kdxrider.net. :bravo:
To post pictures from a device: viewtopic.php?f=88&t=24128
User avatar
Colorado Mike
Gold Member
Gold Member
Posts: 1921
Joined: 11:42 am Feb 25 2005
Country:
Location: Colorado

Post by Colorado Mike »

It could also be that the pilot jet is too lean or clogged. Like Jason said, clean that thing up perfect, set the float level whether you think you should or not. Then see what it does. If you tell us what jets are in it and your altitude, somebody could probably give you an idea if its jetted stupid or not.
Mike

Life's tough, it's even tougher if you're stupid.
'04 KDX220
IdahoCharley
Supporting Member II
Supporting Member II
Posts: 1005
Joined: 06:57 pm Mar 19 2005
Country:

Post by IdahoCharley »

I would try turning in the air screw about 1/2 turn. If the bike idles ok and performs well then it was nothing more than a just slightly lean pilot jet/air screw setting.

Notice any surging when slowing down and using engine braking in 2 or 3 gear?
KTM 380EXC Mine
KDX 200 Mark's
TTR 125 L Wife's
KDX 200 Austin's
EC 300 Tyson's
WR430 Husky - mine
User avatar
KDXer
Supporting Member
Posts: 2845
Joined: 12:11 pm Nov 12 2004
Country:
Location: Sydney, Downunder

Post by KDXer »

I'd also check for any splits or cracks in the airbox boot. Sounds like it could be sucking in air from somewhere.
Image

"I want to die peacefully in my sleep like my grandfather, not screaming in terror like the passengers in his car."
Green Hornet
Supporting Member II
Supporting Member II
Posts: 1455
Joined: 06:54 pm Aug 08 2005
Country:
Location: Orange County-New York
Contact:

Post by Green Hornet »

Sounds like an AIR LEAK, but rip, clean and clean the carb first, then adjust
"Growing Old is Mandatory, Growing Up is Optional"
2008 KLX450R
2008 DRZ400SM
2005 KDX 220R
1985 KDX 200A3
2005 KLX 125L (SONS)
2003 KTM 50SX Pro Jr
B Senior # 254/0092

http://sponsorhouse.loopd.com/Members/R ... fault.aspx
Thanks to my 2008 Sponsers:
Dunlop, SteelMX, Amsoil, Simpson, Pro Works Racing, Pro Moto Billet, SLAP Energy,Boyesen, Rhino Stands, SixSixOne/SunLine Moto for your support.
John W Read Jr
User avatar
fuzzy
KDXRider.net
KDXRider.net
Posts: 3437
Joined: 01:29 pm Jun 18 2003
Country:
Location: Fredneck, MD

Post by fuzzy »

^ I would agree...

Can use WD40 or carb cleaner to find the leak while the engine is running...
'91 KDX 200 Project $300 KDX
'95 KDX 200 Project $600 KDX
'94 WR 250 Always a project
Green Hornet
Supporting Member II
Supporting Member II
Posts: 1455
Joined: 06:54 pm Aug 08 2005
Country:
Location: Orange County-New York
Contact:

Post by Green Hornet »

I would check the manifold area, spray the area like FUZZY said and listen for a change in idle. Make sure the screws are holding the clamps tight enough. Also, clean the inside of the manifold to ensure a clean, tight fit.
Check the floats and fuel valve. Maybe something is out of whack and you are not getting enough fuel, which will give you higher idle.
"Growing Old is Mandatory, Growing Up is Optional"
2008 KLX450R
2008 DRZ400SM
2005 KDX 220R
1985 KDX 200A3
2005 KLX 125L (SONS)
2003 KTM 50SX Pro Jr
B Senior # 254/0092

http://sponsorhouse.loopd.com/Members/R ... fault.aspx
Thanks to my 2008 Sponsers:
Dunlop, SteelMX, Amsoil, Simpson, Pro Works Racing, Pro Moto Billet, SLAP Energy,Boyesen, Rhino Stands, SixSixOne/SunLine Moto for your support.
John W Read Jr
User avatar
KDXGarage
KDXRider.net
KDXRider.net
Posts: 14060
Joined: 06:45 am Nov 01 2004
Country: United States of America
Location: AL, USA
Contact:

Post by KDXGarage »

If all the above fails, check the area behind the stator plate, as there are three depressions which can have a slight leak. Fredette and Gorr mentioned this area. The three areas are on 1989 - 1994 engines where the aluminum and steel heat up at different rates. The areas are suggested to be roughed up and filled in with J-B Weld or similar. Mine had a slight leak there. If you take off the cover and it has an oily mess in there, then you know it is time to fix it.
Thank you for participating on kdxrider.net. :bravo:
To post pictures from a device: viewtopic.php?f=88&t=24128
zkdx
Member
Posts: 26
Joined: 03:02 pm Aug 01 2005
Country:
Location: Arkansas

Post by zkdx »

Thanks for all the insight. I will try all the above mentioned soon. It never surges on me that I can tell, and the boots both look good. I will check them with some WD, then clean my carb again.
04' WR250F--All the standard mods
91' KDX200 (a.k.a. The White Ghost)--not much done yet
01' XR80-kids
01' XR50-kids
85' GS550E--For Sale
User avatar
m0rie
Supporting Member I
Supporting Member I
Posts: 2220
Joined: 10:25 pm Nov 29 2004
Country:
Location: Crescent City, CA

Post by m0rie »

Other things to check include the carb vent hoses (make sure they are not blocked or obstructed), the air filter is oiled and installed correctly and that the pipe/case junction is sealed correctly.

-Maurice
1989 KDX 200
2007 TTR-50E
zkdx
Member
Posts: 26
Joined: 03:02 pm Aug 01 2005
Country:
Location: Arkansas

Post by zkdx »

Thanks all.

Got it fixed. It was just my air screw. Not set right at all, as well as my idle screw. I had no leaks in the boot nor any vent lines blocked or pinched.

I've really been enjoying having a 2-stroke to rip on again, wouldn't trade my wr, but still gotta love the kdx!
04' WR250F--All the standard mods
91' KDX200 (a.k.a. The White Ghost)--not much done yet
01' XR80-kids
01' XR50-kids
85' GS550E--For Sale
User avatar
KDXGarage
KDXRider.net
KDXRider.net
Posts: 14060
Joined: 06:45 am Nov 01 2004
Country: United States of America
Location: AL, USA
Contact:

Post by KDXGarage »

Woo-hoo! I am glad to hear that you got it sorted out. Keep ripping!
Thank you for participating on kdxrider.net. :bravo:
To post pictures from a device: viewtopic.php?f=88&t=24128
User avatar
canyncarvr
Gold Member
Gold Member
Posts: 6943
Joined: 01:07 pm Nov 05 2004
Country: US
Location: The Mythical State of Jefferson

Post by canyncarvr »

Is this where I chime in with, 'I'm glad I wrote up a typically over-long and smarty pants response saying basically 'What IC said, first' (K.I.S.S.)...but it got lost someplace!!'?

Nah!

My point was, on a reasonably well maintained bike a 'hanging idle' will be likely largely due to an air screw/idle adjustment.

Glad it was simple...and that it's done!!

Consider the source
Using a perceived level of knowledge to boost my self worth.
Non impediti ratione cogitationis

bike profile: !clicky!
Post Reply